HOW TO REMOVE DENT FROM A CAR

When you own a car there always come a point in your life when you have to deal with a problem known as dent in a car. many people just get irritated by it and well some pay handsomely
to get it removed some or the other way , and people like me just ignore it as if doesn't exist. The cheapest way is to do nothing. That costs zero. My car has a  few dents... I dont care. They are minor ones. Minor enough they do not rust.  That is my understanding point between repairing or not.

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It depends on the nature of the dent. If the dent is merely the metal or plastic bending in, and can be bent back out, there are strong suction cups designed to pull the dents out. If the dent is deep and the metal round it is creased, then often the dent is very difficult or impossible to pull out, and even if it is, it leaves creases in the metal and paint. These dents often must be hammered back into position. Then the metal or plastic needs to be fixed to be flat (or shaped as they are supposed to).
 To fix damaged metal shape, you first remove paint and primer over the damaged area by sanding.
Once bare metal is exposed, deep spots can be drilled, in order to insert a hook into the hole and pull-out the metal. then Bondo or other auto-body filler can be applied (use many thin layers, allowing to dry between coats then sanding each coat, until the area is built-up and smoothed over.
Once you have built-up and smoothed the area to the desired shape, then the area needs to be primed (a pre-paint paint that helps paint adhere to auto-body filler and metal, while protecting the metal) and then painted.  If the damage has been done on a plastic area of the vehicle, then follow a similar process, except use a plastic adhering auto-body filler.

• If the metal has simply been pushed in and not creased, you can simply use a wet suction cup to pull the dented area back out again. If the metal is creased/stretched but the paint is not cracked or scratched, you can use a hard blunt object to gradually work the damaged area from the back, using firm pressure to gently re-shape the metal. If the damage to the panel is substantial enough that this won't work, your only choice is to replace the panel (inexpensive used at wrecking yards and maybe even in your color?) or use a puller, Bondo and standard body repair techniques to repair the dent and refinish the surface. When doing good bodywork, the key is careful prep and don't rush.

                               (ALSO READ : 10 must have accessories in your car)

• Unless you are comfortable using a welder, body filler, and spraying high quality paint, the best tool for fixing body dents on your own is a nice clean bathroom plunger.
• Clean the surface that has the dent on it, get the plunger stuck on and pull on it and see if the dent pops out.
•  There are other "dent popper" type products sold out there that use suction cups, but they require some skill to use properly.
•  If you feel like spending your money on one to try it, feel welcome to, but if I can't fix a dent with a plunger I just take it in or learn to live with it.

 The most expensive part of repairing dents is usually getting the panel, and the panel around it, painted. However, if there is little paint damage you may be able to use a dent puller to remove it. 

Many body shops offer a service called Paintless Dent Removal which is usually much cheaper than doing it the traditional way.

CREDIT : FEW QUORA WRITERS AND SOME MY EXPERIENCE. 

(FULL DISCLOSURE : IMAGES ARE FOR REPRESENTATIONAL PURPOSE ONLY AND I DON'T OWN THEM  IF YOU ARE THE OWNER AND YOOU WANT IT REMOVED LET ME KNOW I'LL DO THAT)